Process of treating ores containing precious metals.



FREDERICK WILLIAM MARTINO AND FREDERIG STUBBS, or SHEFFIELD, ENGLAND.

PROCESS OF TREATING ORES CQNTAINING PRECIOUS METALS.

SPECIFICATION forming part of Letters Patent No. 635,793, dated October31, 1899.

Original application filed December 23, 1898, Serial No. 700,10'7.Divided and this application filed July 25, 1899. Serial NO: 725,083-(No specimens-l To all? whom it may concern:

Be it known that we, FREDERICK WILLIAM MARTINo and FREDERIO STUBBs,subjects of the Queen of England, residing at Sheffield, county of York,England, have invented certain new and useful Improvements in orBelating to the Treatment of Ores Containing the Precious Metals, (forwhich we have made application for Letters Patent in Great Britain, No.25,979, dated December 8, 1898; in Ger many,filed December23, 1898; inNew South Wales, No. 9,109, filed March 22, 1899; in Victoria, No.15,996, filed March 20, 1899; in Queeensland, No. 4,848, filed March 23,1899; in South Australia, No. 5,848, filed March 20, 1899; in WesternAustralia, No. 2,428, filed March 17, 1899; in New Zealand, No. 11,486,filed March 28, 1899; in Transvaal, No. 1,834, filed March 11, 1899; inCanada, No. 84,874, filed February 28, 1899, and in Hexico, filed March28, 1899,) of which the following is a specification, it being adivision of our application, Serial No. 700,107, filed December 23,1898.

This invention relates to the treatment of ores or tailings containingthe precious metals, its primary object being to set free the preciousmetal prior to its extraction,when it is combined with or intimatelyinclosed in the metalloids or the baser metals.

The essential feature of this invention is the employment of calciumcarbid in the treatment of the ores.

When the precious metals are combined with or intimately inclosed in themetalloids sulfur, selenium, tellurium, phosphorus, silicon, &c., or thebaser metals, such as arsenic and antimonythe ore is finely divided andthoroughly mixed in a dry state with calcium carbid. The mixture is thenmoistened, the result being that acetylene is generated, accompanied byconsiderable heat. By the action of the acetylene hydrids of themetalloids or baser metals are formed, leaving the precious metal in thefree state. The free precious metal may be treated in any convenientWay. Preferably the coarser metal is separated by washing and the finerparticles dissolved in a oyanid solution, which is then subjected to theaction of acetylene or calcium carbid according to the process describedin our United States patent application, Serial No. 700,107, filedDecember 23, 1898. This treatment of the finely-divided ore with calciumcarbid is also applicable to silicious or quartzy ores or tailings,where minute particles of the precious metal are inclosed in a casing ofsilica.- The casing is opened up by the action of the carbid, leavingthe gold exposed, so that it may be acted upon by any desired solvent.

The intimate mixture of ore and calcium carbid, either before or aftermoistening, may be heated in any convenient form of furnace, and suchheating is found to accelerate the process. The following are thechemical reactions which probably take place in the process according tothis invention, telluride of gold of the probable formula Au Te beingtaken as an example: When dry calcium carbid is mixed with the tellurideof gold and the mixture then moistened with water, the telluride of goldis decomposed into gold and tellurium hydrid, the reaction being expressed by the following equation:

The free gold can, as stated above, be extracted in any convenientmanner.

WVe claim- The treatment of ores or tailings containing the preciousmetals by finely dividing the ore mixing it with calcium carbid andmoistening the mixture with water substantially as described.

In testimony whereof we have hereto set our hands in the presence of thetwo subscribing witnesses.

FREDERICK WILLIAM MARTINO, FREDERIO STUBBS. Witnesses:

Josnrn BRIGHT, THOMAS HARVEY.

